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Full text of "The protection of structural metal."

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The Protection o/ 
Structural Weti 









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/fLL Illustrations in this Booklet are 
_zl of Buildings or other Forms of Con- 
struction upon which Red Lead^ 
was used as a Protective Coating 



Copyright 1912 
O. C. Hakn 



Difference in Paints 



MISUXDERS'J VNDING of what paint is, what it ran be 
reasonably expected to accomplish, and how it performs 
its duty in preserving and beautifying objects, is respon- 
sible for a great loss of money, both to the small property 

uwiht and the great manufacturer. 

To the average person paint is paint, and the first error to which 
this lack of discrimination leads is the use of the same paint for all 
purposes and under all condition-. 

That pure white lead and pure linseed oil, mixed properly to suit 
the special conditions under which the paint is to lie used, is the besl 
possible protection for wood, brick and cement, cannot be gainsaid. 
But when it comes to the painting of a metal surface, white lead, 
though good, must yield first place to red lead. 

To show fully just why this is s<> would require a long explanation 

osion is, a comparison of proposed methods to stop or 

retard it and an intricate examination of the chemical and physical 

properties of various materials. This would be out of place in a 

lical hand-book designed for the daily use of the architect, engi- 

neer and painter, such as this little booklet aims to be. 

Enough of the theoretical phase of painting metal surfaces must 
_iven, nevertheless, to satisfy the intelligent inquirer thai the 
methods recommended are scientific. 

Tendency of Metals to Corrode 

The relative tendency of various metals to corrode or oxidize is 

shown by the following table; those which corrode most easily being 
placed first and those which resist corrosion more successfully follow- 
ing in their order. Zinc, the most easily corroded, is thus at the top, 

and gold, the most resistant, at the bottom of the list. 

Zinc Hydrogen 

Uuminum Copper 

I idmium Mercury 

Inm Silver 

Steel Platinum 

\irkel Gold 
Lead 

In practical affairs iron; in one form or another, is the metal prin- 
cipally used. By the above list it will be seen that iron is one of the 




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most readily corroded. Our attention will be given entirely, there- 
fore, to this metal, either bare or covered with a coating of tin or 
zinc. 

Decay, Both Internal and External 

Iron and steel, then, are subject to decay. That is to say, they 
are liable, under certain conditions, to lose some valuable quality 
which weakens them. If this loss is internal it may be caused by 
what'is called "fatigue," due to loss of strength through strain. This 
cannot be prevented by painting. If the decay is external it is due 
to oxidation of the surface; i.e. the metal rusts. This can be pre- 
vented by proper painting. 

Iron and steel will not rust at ordinary temperatures except in 
the presence of moisture; therefore, contact of water or moist air 
with the metal is the. thing to be feared and, if possible, prevented. 
Water and air are known as the primary causes of corrosion. To 
these must be added a number of secondary causes or accelerators of 
corrosion, such as, first, rust itself, because it absorbs and holds 
moisture to the surface; second, carbonic and other acids; third, 
neutral or acid salts in solution; fourth, roughness in the surface; 
fifth. matter, such as scale, on the surface; sixth, inequalities 

in surface conditions due to imperfectly made metal; seventh, stray 
. •](•<•! ric currents. 

Methods of Preventing Rust 

Rusting i- a galvanic or electric action and the ill effect of all these 
secondar; 'lerators of corrosion is due, in t he final analysis, 

to electric action which they set up in the iron or steel. If we could 
.t«,|> the electric action produced in iron under certain conditions, 
there would he no corrosion and iron would become a noble metal. 
I | can be done temporarily by immersing the iron in an alkali 
solution; bu1 as soon as the iron is taken out, it rusts as before. The 
line-solution method of preserving iron is therefore impracticable 
for mosl purposes. To use alkalies in paints is not practical because 
they decompose the oil and are soluble in water. 

Another method by which the galvanic action can he prevented 

is lo treal the iron with solutions of chromic acid or certain forms 

.ncent rated nitric acid. Hut this treatment, also, at the present 

is found to be of but temporary value, for the iron 

.dually returns to its original state, in which it rapidly corrodes. 

Both the above methods attempt to change the nature of the iron 
itself and render it immune to galvanic action. They are interesting, 
nid some day a method may be found to render permanently effect- 
ive the change which they undoubtedly make in the iron itself. But 
until tha aes we arc compelled to leave the nature of the iron 

1 1 is and protect it from the causes which set up the electric action 
within it. In other words, we have to paint it. And the paint must 





ll 




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be made of some material which will not itself start galvanic action 
by contact with iron and which will effectually keep out water or 
other injurious elements. There are several candidates for selection 
a^ protectors of metals from corrosion. Before examining them 
specifically, let us observe what the requisites of a good paint for 
iron and steel are. 

What Constitutes a Good Paint 

Asking this question regarding preservative coatings for iron and 
we find it necessary to point out that a paint which may be a 
good paint for the under coaN may prove to be an undesirable paint for 
the outer or finishing coats, and vice versa. We will call the paint 
which is to go next to the metal the "protective paint," and the paint 
which comes outside, the "finishing paint." The finishing paint 
should be, in reality, a "protective paint" also, but, for clearness in 
discussion, it is necessary we should make a distinction. 

The protective paint should measure up to the following 

( i E X E R A L Q U ALIFIC ATIONS : 

First — It should form a hard, adherent foundation for subsequent 
coats. There i> nothing else which tends so much to the cracking, 
checking ami alligatoring of paint as the application of relatively hard 
coats over relatively soft coats. This is an observation which should 
he kept in mind not only in the painting of metals but in all painting. 
That the priming coat should have the power to adhere tenaciously 
to the surface is self-evident. 

Second — The pigment constituents of a protective paint should he 
inhibitive of corrosion. This means that it should tend to give pas- 
sivity to the particles of the iron itself— should by its nature tend to 
prevent that activity of molecules which we have described as gal- 
vanic and which causes corrosion. 

Third— A protective paint should be a non-conductor of electricity, 
>sion of iron and steel being the result of a galvanic action. 
it is necessary not only to put on a paint which will be inhibitive, 
that is, keep out those influences which will set up the galvanic action 
in the iron itself, but it i- supremely necessary also to bar the way to 
stray electric currents from the outside. In these days when electrically 
'Inn urn r\ crvu here, under the streets, overhead and through 

all buildings, the leakage of electric currents is an everyday problem. 
The real solution of the problem would seem to be to confine these 
electric currents where they belong instead of allowing them to run 
riot neighboring property. Motives of economy itself will 

doubtless some day lead the owners of the runaway electricity to 

ed this evil themselves, but until that day arrives, we must do 
our best to protect our property against currents which are running 
amuck. 



■■ 





NATIONAL BISCUIl COMPANY BLTLDIM. 
Kansai City. M<. 



Some pigments are good conductors of electricity. These should 
be avoided in paint intended for the protection of iron and steel. 

Fourth— A protective paint should contain no compounds soluble 
in water. The reason for this is apparent. If any of its constituents 
is soluble in water, which is one of the chief enemies we are fighting, 
the paint will soon go to pieces under service conditions. Water- 
soluble compounds may also, under certain conditions, unite with 
other elements to form new compounds favorable to the conducting 
of electricity. 

Fifth—A. protective paint should be as impertneable as possible. 
This qualification scarcely needs comment. One prime purpose of 
a protective paint is to keep out water. If it is porous, moisture— 
a principal cause of the galvanic action which causes rust— will find 
easy entrance. 

Sixth— Protective paint should vary in color in its different coats. 
This is one of the most important requisites of a protective paint, 
but one which is very often overlooked or ignored. Poor workman- 
ship is responsible in very great part for the failure of protective 
coatings. Paint is often applied by cheap and inefficient labor, and 
if each successive coat of paint is of the same color as the preceding 
one, it is impossible for an inspector to detect slighted parts. Above 
all, the first coat should be very different in color from the natural 
color of the metal and the finishing coatings should be different from 
the protective coats. 

Available Paints 

There are several materials in more or less general use as protect- 
ive paints for metals. A brief examination of the nature of these 
materials will enable us to see how they measure up to the standard 
set by the foregoing requirements. 

Linseed Oil.— Linseed Oil, without a pigment, is sometimes 
recommended as a priming coat for iron or steel, but such a practice 
cannot be too emphatically condemned. Linseed oil is the best 
vehicle to use with a good pigment, but when used alone it fails to 
meet four of the important requirements given. 

In the first place, linseed oil forms a film which always remains 
soft as compared with later coats containing pigments. The cracking 
• lligatonng of the subsequent paint is almost inevitable. 

In the second place, linseed oil is not an inhibitor of corrosion 
and it separates the iron and steel from the subsequent paints, thus 
nullifying any rust-inhibiting power which the later coats possess. 

In the third place, it is more or less porous and, the film being 
thin, it is permeable 

In the fourth place, linseed oil is transparent, making it almost 
impossible for an inspector to tell whether or not the surface has 
been perfectly protected by it. 




<>h^ 






Mineral Oils. — No mineral oil or non-drying oil of any kind 
should be used in a protective coating. They prevent the paint from 
becoming sufficiently hard to give a good foundation for subsequent 
paint. Linseed oil, when used alone, as we have seen above, makes 
a soft film, but when used with a pigment, especially if a part of the 
oil is boiled, the film will dry hard. Linseed oil, therefore, should 
be used with a pigment in all protective coatings. 

Asphaltum 

An objection to asphaltum, as sometimes used, is that it tends to 
work through subsequent coats; and if used as an ingredient of a true 
oleo-resinous varnish, it requires much oil, and does not make a coat- 
ing hard enough to serve as a substantial foundation for subsequent 
coats. If the under coat is too elastic and yielding, the other coats 
will crack. It i-. it" of fairly durable quality, very difficult to apply; 
in cool weather, impracticably so. 

It is further to be observed that all asphaltum paints are thinned 
with turpentine (usually ''mineral turpentine") or benzine, for which 
the customer has to pay, but which evaporates entirely. The result 
is, that to get a coat of protective thickness he has to apply twice as 
many coats as of red lead; or else he has to apply a coat of such 
viscidity that twice as much of it will adhere, which makes difficult 
painting and uses up so much paint that it is a costly material, even 
though sold at a low 7 price per gallon; not only is a large amount used, 
but a man can apply it to but a small area in a day's work. This is 
a serious matter. These paints are essentially varnishes; and all 
house painters and decorators know that varnish paints are lacking 
in body, and that three coats of such paints arc not more than equal 
to one coat of a straight lead and oil paint. A good asphaltum paint 
is the most difficult to use, therefore, and more of it is required than 
of any other paint. 

Graphite and Carbon 

These do not in themselves have inhibitive qualities; and while 
some grades of them are valuable ingredients in certain paints, they 
are not the best materials for use alone, especially as basic coats on 
metal. Graphite is almost always coarsely ground, which i> a serious 
ct in any paint; and the naturally fine sorts of carbon require 
much oil; some of these paints contain less than a pound of pig- 
ment in a gallon; such preparations are only a sort of wash, yet on 
account of their intensity of color, they will appear to conceal the 
metal although excessively thin, — too much so to afford much pro- 
tection. Finally, the similarity of color between the paint and the 
dark surface of the iron makes it difficult to detect imperfections in 
the application of such a paint. First coat paint on iron should be 
of a brilliant color, in which defects will show instantlv. 



— 



/.-^^s 




• 



Iron Oxides 

The oxides of iron would be fairly good materials to use in pro- 
tective coatings, provided they were fully dehydrated and contained 
no sulphur compounds, especially sulphate of calcium, which in the 
presence of moisture is a fairly good conductor of electricity and there- 
fore acts as an accelerator of corrosion. This soluble sulphate also 
carries sulphuric acid to the metal surface. On wood this is of less 
importance; but in the presence of moisture and carbonic acid it will 
corrode iron, and is a seriously objectionable ingredient. 

Sometimes oxide-of-iron paints are made from by-products of 
sulphur compounds and, to offset the evil due to the presence of the 
sulphur, carbonate of calcium (chalk or whiting) is often added. 
This practice, however, is not to be commended, for soluble calcium 
sulphate will then be formed, and soluble compounds, as we have 
seen in our list of requisites, are bad for a protective coating. The 
solubles help to carry moisture to the surface of the iron, and moisture 
sets up the galvanic action which produces corrosion. Besides the 
above objection, the calcium carbonate destroys the oil in the paint 
film, and has no place in any oil paint which is to be durable. Theo- 
retically good iron oxide- dehydrated and sulphur-free — is seldom 
seen in practical use, as results show. It will be seen, therefore, that 
the difficulty in the case of iron-oxide paints lies not so much in the 
inferiority of theoretic or perfect oxide of iron itself as in the fad thai 
the iron oxides obtainable cannot be relied upon as free from injurious 
constituents. Iron oxides are, moreover, of like color to iron rust, and 
the latter does not show readily through or beside such paints. 

Red Lead's Qualifications 

We now come to consider red lead and to judge it by the same 
standard of requirements which we have applied to the other materials. 

In the first place, there is no paint which makes such a good, hard, 
tenacious film as red lead. For this one reason alone many painters 
prefer it for general painting, even of woodwork, brick, etc. Red-lead 
paint dries to a hard, tough layer and gives the best foundation for 
other painting that has been devised. Over it almost any kind of 
paint can be applied. It forms an especially good foundation for 
varnishes, varnish paints, enamel paints and all other forms of deco- 
rative painting. Over a pure linseed oil and red-lead paint the 
tendency to check and alligator is negligible. The red-lead paint 
adheres to the metal with a tenacity that is remarkable. When 
attempting to clean old metal one often finds the red lead cling 
so fast that it cannot be removed even with wire brushes. 

In the second place, red lead is unquestionably the most practi- 
cable inhibitor of corrosion available as a constituent of protective 
coatings. This is probably because it is a chemically basic material, 
and any carbonic or other acids in the air or water which penetrate 
the paint, are taken up by the lead before they can attack the iron. 

15 



No other paint does this. White zinc might, in theory, do so, but it 
is never used because it scales off from iron; iron oxides, if attacked, 
simply pass the acid on to the metal. The lead oxides, red lead and 
litharge, are the only things which will practically take up the acids 
and absorb them, thus preventing them from reaching the metal 
surface. As long as red lead is present, in contact with the iron, the 
latter is protected. 

In the third place, it is an excellent insulator and is practically 
indispensable for painting metal where electric currents are present 
in unusual quantity. A German scientist, writing in the Farben 
Zeitung, says: "Red lead is remarkably impervious to electricity of 
high tension, bring fully equal to the best India rubber or gutta- 
percha, ;in an insulating material/' 

In the fourth place, pure red lead mixed with pure Linseed oil 
makes a paint which contains no constituent- soluble in water. It 
therefore passes our fourth requirement with a perfect score, 

As to the fifth requirement, impermeability, red had stands espe- 
chilly high. In order to secure a greal degree of impermeability 
of the paint coats must have ;i reasonable thickness. If the paint Is 
brushed out too thin, one or more additional coats must be applied to 
give proper thickness of coating. The working qualities of red lead 
mixed with linseed oil are such thai the film spread with il i- "I 8 
superior character. 

Impermeability is also affected by the amount of pigment presenl 
in the film. Generally speaking, the greater the amount of pigment, 
the more impermeable the paint will be. The increase of the propor- 
tion of pigment to oil must stop, of course, when the paint becomes 

unworkable. Red lead LS noted lor the large quantity I >i il which 
can be mixed with a gallon of linseed oil ami still • ' working 

paint. 

Furthermore, it has beeE found that the finer the pigment, the 

more impermeable the paint; bill the fineness of the pigmenl 

be increased beyond what will permit the presence of a -nil 
quantity of pigmenl in the paint. Red lead as \\<' make it is an 
edingly fine, uniform pigment and yet makes a splendid! 

paint at the proportion of four parts pigment to one pari "il 

Red lead and oil dries rapidly ami throughout, not superficially, 
in this way differing from other paints. It can. therefore, be used 
in places where other paints dry imperfectly and partially, and it is 

net surpassed by any in the most favorable situatii 

th< ability 

thick f i 1 1 1 minimum 

ehicle an< e make it. it is a fine, uniform pigment. 

lirement is met perfectly bj red lead. It baa the 

ed afl 
paint- for metals. Its bright orange hue is readily from 

or black of iron ai I an admii 






priming paint, considered from this point of view. An inspector can 
readily see whether any spots have been left uncovered. The second 
coat of red lead can be slightly tinted with a few ounces of lamp 
black, thereby rendering it distinct from the first coat. On the third 
coat one may return to the natural orange red of the red lead, or 
deepen it still further with lamp black. 

Objections Sometimes Raised Against Red Lead 

It is said that red lead is difficult to use; that it is so heavy it runs 
down on vertical surfaces, and that it must be mixed with oil at the time 
of UMn- or rise it will set hard in the pail. Some red lead may do these 
things, but not red lead properly prepared for painting purposes, I 
the red lead is coarse the paint will run, but red lead can now be sup- 
plied uniformly fine, and the finer it is the better. If mixed with too 
much oil it will run, and it is sometimes said that if mixed with a 
proper amount of oil, it will set or thicken while using; but if tin- is 
so it is because it contains too much litharge. If a high grade of red 
lead is used, it does not thicken in the pail, and it works smoothly 
under the brush, and can be kept tor day- without appreciable eh;: 
'Mir extremely line powder now made containing a very small propor- 
tion of litharge, used in the proper proportion with oil, makes a paint 
of excellent working quality; it is above criticism and entirely different 
from the inferior grades of some makers. It is sometimes complained 
that on exposure to the weather it turns white, and that this indicates 
decomposition; but, in fact, this whitening is only the conversion of 
the surface into white lead, which is a good paint itself, and which 
has so strong a covering power that an excessively thin superficial layer. 
probably not more than one ten-thousandth of an inch thick, is enough 
to show; so that the change, which is not important anyway, i- in- 
considerable in amount. 

What Red Lead is and How it is Made 

Red lead is an oxide of lead and if of theoretical purity, contains 
90.65 per cent, of lead. Its formula is l'l.O. and apparently it is 
plumbate of lead, formed by the combination of peroxide of lead 
(Pb0 2 ) and litharge (PbO). It is a red powder varying in color from 
a light orange to a dark red. 

\ piece of lead pipe bearing the imprint of the Roman Emperor 
Vespasian, and found in good order after lying in the earth more than 
1800 years, offers pretty good proof that metallic lead, at ordinary 
temperatures, is immune from oxidation or rust. 

The fact seems to be that, in the presence of moisture, a film of 
oxide does form on the surface of metallic lead, but that this film 
itself tends to protect the metal from further oxidation. 

But what is true of lead at ordinary temperatures does not hold for 
lead in the molten state. Here it oxidizes quite readily. The higher 

17 



the temperature up to a certain limit the more rapid the oxidation. 

Two common forms of lead oxide are known as litharge and red 
lead. These are manufactured in reverberatory furnaces, that is, 
furnaces in which the heat is reverberated or thrown down from the 
arched roof of the furnace upon the material which is to be treated. 
The hearth or space where the oxidation occurs is about ten feet 
square. The fire boxes are at the sides. The arch is three or four 
feet above the hearth. 

The manufacturing process begins by placing about one and a 
half tons of metal lead in one of these furnaces. The melting begins 
at about 620° F., but there is not much oxidation until the tempera- 
ture is raised considerably. It is often raised as high as 1000° F. 
before the oxidation is complete. 

While the lead is molten it is constantly stirred with huge iron- 
handled hoes in order to expose all parts of the lead to the oxidizing 
action of the air. Gradually the molten mass becomes granular, and 
with continued heat, all the lead is converted into oxide If the heat 
has been high enough to render the litharge pasty, it will, when 
cooled and removed from the furnaces, break down into small reddish 
yellow flakes, known as flake litharge. When this substance is pul- 
verized by grinding it takes on a buff color. 

The process of transforming metallic lead into litharge requires 
about 24 hours. In thai time with the temperature at from 11 on- 
to 1600°, the lead has taken up all the oxygen it will then hold. The 
oxidation for the time being is complete. But here is a remarkable 
fact: If the buff-colored, powdered litharge be again heated up to 
about 900° F., it begins taking on more oxygen and changes in color 
to a brilliant red. This is red lead. 

More remarkable still, if the temperature be raised to lino' and 
hi-her. the red lead loses the added oxygen it had absorbed and goes 
back to litharge. 

For readers who are interested in the chemistry of the subject it 
may be said that litharge, PbO, is monoxide of lead. To two parts 
of PbO there is added one part of Pb()», peroxide of lead, making 
plumbate of lead, PbiO*. 

Usually, in the conversion of litharge into red lead, not all of the 
litharge is converted. There may be a small remnant of the latter, 
but red lead paint should contain less than ten per cent, of litharge 
and more than ninety per cent, of red lead, and preferably be more 
highly oxydized than this. 

there is one form of red lead, using the term in its generic sense, 
which is made by the oxidation of white lead. This is known as 
orange mineral, and, on account of its original fineness and its 
amorphous condition, is more readily oxidized and, consequently, 
usually contains a lower percentage of litharge than red lead made 
from metallic lead. 

19 



Red Lead's Relation to Linseed Oil 

The nature of the relation between red lead and linseed oil in 
paint is a matter of some dispute. It is believed by some that red 
lead forms a cement by combining with the linseed oil. It would 
seem, on the other hand, that this combination only takes place in 
proportion to the free litharge present and not between the red lead 
and the linseed oil. 

I appears also that much of the character of red-lead paint is 
t-n to it by the effect the red lead has upon the drying of the oil, 
the lead and* the oil drying all the way through, while a manganese 
drier dries on the surface. It has been suggested that the boiled oil 
used with red lead should contain no manganese. This may be a 
good practice. It seems more likely, however, that the amount of 
lead present is sufficient to overcome any tendency towards surface 
drying given to the boiled oil when manganese is present in it. 

The Uses of Red Lead 

One might cover the uses of red lead as a protective paint for 
metals in the words: " Wherever metal is used." It may be profit- 
able, however, to enumerate some of the more important he Ids in 
which a protective paint is required and call attention to some oi the 
considerations peculiar to each. 

Structural Iron and Steel 

The architect and engineer are probably more vitally interested 
in the proper paint for metal work than any other class oi paint users 
for more serious consequences follow a mistake upon their part. JNot 
onlv may vast sums nf money be lost through the imperfect protec- 
tion of the iron and >Uh-1 skeletons of their structures, but human life 
itself hangs upon the proper preservation of those great steel frames. 
An architect or an engineer may correctly figure the stress and 
strain, and the manufacturer may conscientiously turn out steel ot 
the finest strength and quality, but unless rust is kept torn the col- 
umns, beams and girders, the strong, safe skyscraper of to-da> maj 
become a death-trap a few years hence. 

An excuse which might pass muster if only ordinary business risks 
were involved is utterly inadequate to defend the use of a substitute 
for red lead. 

Thus one sometimes hears an excuse like this: "Yes, I know red 
lead is the best paint for metals, but what I use is more convenient 
and I guess it does pretty well." 

In the face of what is at stake, it is scarcely conceivable that any 
responsible man could make two such admissions in the same breath, 
namely, that "red lead is the best," but "I am using something else. 



21 







. 






Should Steel Imbedded in Concrete be Painted? 

It is often asked: Is the imbedding of structural iron or steel in 
concrete sufficient to prevent the rusting of the metal members, or 
should the latter be painted before they are surrounded by the 
concrete? 

We have seen in our brief discussion of the nature of corrosion and 
the remedies for it, that alkaline solutions tend to change the nature 
of tin- iron and render it immune to the galvanic influence which pro- 
duces rusting. It would seem, therefore, that the caustic lime in the 
cement should itself be the besl possible insurance against the decaj 
of the iron imbedded in it . A- a matter of fact, what we would expect 
does take place and as !<>tnj as the cement remains caustic the metal is 
perfectly immune t< on. The difficulty is, the cement does not 

remain caustic. It absorbs carbonic acid from the air and the caustic 
lime becomes converted into insoluble carbonate of lime, which i> a 
poor preventer of corrosion. 

Protection of the iron by means of the concrete would be possible, 

also, only as long as there is perfect contact with tin' metal. This in 
practice is very difficult to attain or maintain. It is seldom, in the 

average structure, that voids or open >[i;icc> are not presenl between 

the iron member and the surrounding concrete. Usually the contact 
i- nol perfed at the beginning and the chemical changes caused by 
the absorption of carbonic acid l>\ the concrete, cause a loosenii 
the bond between the iron and concrete, even where contad at first 

ood 

Through these spaces moisture-laden air flows and < 

i leaky roofs, scrubbing brushes, water-pipes, drains and steam 

eeps down, causing corrosion. For the same reasons, the 
of structural iron in shaped brick is inefficienl to pr< 

ion. 

If complete imbedding of the iron or steel in a -ood non j 
which can be kept caustic is not practicable, the metal : 
should be painted with red lead before encasing them. 

Iron and Steel Bruises 

I •• is no structure which needs the best possible prot< 
painl more than a steel bridge. Whether maintained by a railroad 
or by the people, represented by their county commissioners or < itv 
department, economy of up-keep should be of the utmost inter* 

A paint which gives perfect protection to a metal makes a I 
tically permanent, SO far as the ravages of the weather arc con 
cerned lis use is therefore economical, no matter how much cheaper 
the firsl institutes may be. led lead i- the only prote< 

painl which ha- been shown to be an absolute rust preventive. 




a Railroad at ) 
Bascule Bridfc 



Gasometers and Stand Pipes 

The desire for economy which influences great railroad corpora- 
tions to use red lead to protect their bridges and other steel structures, 
should persuade gas companies and water companies to use the same 
material for painting the exterior of gasometers, stand-pipes, tanks, 
etc. 

Other paints may he had which will show lower first cost, but 
there, is none which will maintain the plant at such a small expendi- 
ture per year. Red lead is a real preservative of iron and steel. 

Metal Roofs 

There is no metal used as roofing, except lead and copper, which 
can stand the weather without being painted. Tin, galvanized iron 
or steel should be coated with red lead and linseed oil as hereinafter 

explained in detail. The roof need not be left the natural color of the 
red lead if that color is undesirable. If a light tint is wanted, white- 
lead paint tinted to any desired shade is the paint for the finishing 
coats; if a dull red or brown is suitable, the last red-lead coat may 
be toned with lamp black. 

Cornices and Other Galvanized Iron Work 

Galvanized iron presents difficulties in painting because the coat- 
ing left on it by the galvanizing process seems to repel most paint. 
Red lead and linseed oil paint will stick to it better than any other 
material. Cornices or other parts made of galvanized iron should be 
allowed to weather or be treated with a special solution, as described 
on page 39, before painting. Red-lead paint should thru be applied 
as to iron. 

Interior Metal Work 

Steam radiators, registers, pipes, grille-, water-tanks and every 
piece of exposed metal work inside of a building should be painted 
first with red-lead paint, then finished with high grade paint Mich as 
white lead and linseed oil, tinted to suit the color scheme of the room. 

Fire Escapes, Fences, Etc. 

Fire escapes, fences, iron gates, grilles and ornamental exterior 
metal work of all kinds should be painted with red lead and linseed 
oil. 

Red Lead in the Factory 

Besides its use on the structural members of the building itself, 
the contents of a factory frequently require red-lead paint. Machinery, 
trucks, iron pipes, tanks, etc., on the interior, and stand-pipes, con- 

25 



veying machinery, derricks, etc., out-of-doors, should be painted 
with pure red lead first and finished with red lead toned with lamp 
black, or with whatever finishing paint best suits the conditions. 

For Steel Cars 

For steel cars red lead is the ideal paint, not only because of its 
general anti-rust qualities but because it makes a hard film which 
resists in a superior way the friction and hard knocks to which such 
cars are subjected. 

Painting of Steel Ships and Boats 

Nowhere has red lead proved itself more of a property-preserver 
and money-saver than in the painting of the hulls of steel ships and 
other metal parts of such craft. From the United States Government 
to the maker of the smallest craft, vesselmen are constant users of 
red lead in enormous quantities. Whether on salt water or the great 
inland seas, red lead stands out as the great ship paint. Many proofs 
of the truth of this statement could be adduced, but none stronger 
than the fact that marine insurance companies have in many cases 
cut the valuation down on a large number of steamships because 
corrosion has been allowed to get into the bulkheads and other parts 
of the ships. 

The hulls, cargo holds, coal bunkers, chain lockers, and, in fact, 
all metal parts of ships should be painted with red lead as hereinafter 

described. 

The demands made upon the protective coating of vessels are 
most trying. Not only is the hull in the water, but there is the 
friction against docks in the landings, the rough usage which the 
holds receive in the moving of freight and, withal, the exposure to 
varying atmospheric conditions as the vessel sails from place to place. 
It is a significant fact, therefore, that the standard protective coating 
for vessels both in the fresh water of the Great Lakes and the salt water 
of the oceans, is red lead. Last coats of other materials are frequently 
used because of their greater adaptability to decorative demands or 
because of power, real or fancied, to prevent fouling of bottoms. 
White lead, either natural or tinted, is necessary for last coats when 
light tints are desired, and lamp black is excellent if black is preferable 
to the orange peculiar to red lead. 

But custom is pretty well agreed upon red lead for the coat which 
goes next to the iron or steel. The reason has already been explained 
in connection with the protection of these metals in other work. 

re is no paint which dings to metals so well as red lead. 

The best proof of the superiority of red lead paint for all metal 
parts of vessels is its general use for that purpose bj the United 
3 Government and an overwhelming majority of vessel owners, 
both on the seaboard and on the Great Lakes. 



It is an interesting practice among owners of great freighters, 
especially on the Great Lakes, to mix white lead and red lead for the 
finishing coats in the holds. This is done to secure the wearing 
quality of red lead and at the same time the light tint which the 
white pigment contributes, thus making the dark hold lighter. 

How Much Red Lead to the Gallon? 

The practice of various architects, engineers, vessel builders and 
owners, painters, etc., in regard to the formulas used in mixing red lead 
paint varies. The United States Navy Department has general 
specifications which allow about thirty-one pounds of red lead to the 
gallon of linseed oil. From this the formulas run both w T ays, up to 
thirty-three pounds to the gallon and down to twenty-five pounds 
to the gallon. Good results are had by all, but it has been seen that 
one of the great desiderata in a protective paint is richness in pigment 
as compared to oil. Therefore, it is evident that those who take full 
advantage of red lead's power to mix well with a small quantity of 
oil are securing the greatest benefit. Only exceptional conditions 
really justify the risk of the smaller proportions of pigment sometimes 
used. We recommend not less than twenty-eight pounds of red lead 
to the gallon and we consider thirty-three pounds to the gallon as 
the best for all general purposes. But this red lead must be of the 
highest quality. As has been already pointed out, if as much lead 
as this per gallon is used of an inferior lead (some of which is one- 
quarter litharge) great trouble will be encountered in applying it. 

From time to time inquiries are made as to the amount of red lead 
paint required to paint a ton of steel. This is impossible to determine 
with any accuracy as it will run from y 2 gallon up per ton for three 
coat work, according to the w T eight and shape of the steel and the 
surface consequently exposed. 

Laboratory and Field Tests 

Among the most conclusive laboratory experiments for the pur- 
pose of testing protective paints is that reported in the Journal of the 
Society of Chemical Industry of December 30, 1899, page 1093. It is 
contained in an address on "Protective Paints for Iron" by Harry 
Smith, F. I. C, before the Newcastle Section of the Society of Chem- 
ical Industry at the Durham College of Science, England. 

Perfectly Protected by Red Lead 

Three tests were made: (1) Shallow iron dishes were painted 
with the various paints and filled with water, which was allowed to 
evaporate. As fast as the water evaporated the dish was refilled. 
During the three months of this severe test rust was formed on all 
the dishes except those protected by red lead. Those dishes protected 
by linseed oil alone were the first to corrode and produced the greatest 
quantity of rust. 

27 



■ 



-* 








1 



In the second test painted plates were exposed to the weather for 
twelve months. This was a mild test and, with the exception of 
those coated with oil alone, no great deterioration was observed on 
any of the plates. 

In the third test, strips of sheet iron received two coats of the 
same paints used in the first two experiments and were immersed in 
water ior three months. The amount of rust in each bottle was 
accurately weighed and calculation was made on the basis of pounds 
per *1500 square feet . 

Again red lead was the only paint out of thirty-seven to come 
out with a perfect score. There was absolutely no corrosion of those 
strips protected by red lead. 

Of the other pigments, deep iron oxide allowed 123 pounds of 
rust; middle iron oxide, 134 pounds; extra bright iron oxide, 137 
pounds; pure graphite, 215 pounds; Indian red (oxide of iron), 227 
pounds; ivory black (carbon), 250 pounds; turkey red, 262 pounds; 
boiled linseed oil, 500 pounds. 

Ranging between these at various points were various pigments 
and mixtures of pigments. They are of no particular interest as no 
one now seriously recommends any of them. It is interesting, however, 
to observe that white lead, zinc oxide and lithopone, which are not 
urged as metal protectives, proved superior to all of the so-called 
protective coatings except red lead. The latter was in a class by 
itself, being the only one to protect the iron perfectly. 

Mr. Smith also referred to another test he had made two years 
before, in which red lead again was the only paint which allowed no 
corrosion whatever. It was in perfect condition after two year-. 

A Five Year Service Test 

One of the best field experiments coming to our notice was that 
ma ,l,. } , x Mr U D. O Keefe, superintendent of bridges, Fort Huron, 
Mich. To decide what protective paint the city should use, Mr. 
O'Keefe painted half of one bridge with our pure red lead and the 
other half with graphite. At the end of five years, the red lead was in 
perfect condition, the graphite was washed away and the steel was 
badly pitted and rusted. All the Port Huron bridges are now painted 
with red lead. Here is Mr. O'Keefe's letter. 

Port Huron, Mich. 
Sirs- Five years ago I had the lower part of Military Street Bridge painted with your 
pure red lead and linseed oil, and the upper part with a graphite paint, for a test and am 
pleased to inform vou that the red lead is in first, lass condition and has kept the bridge 
from corroding, while the other paint used on the upper part did not give satisfaction as 
it would not stand the acid which comes from the river. We are going to paint all the 
other bridges in the city, and am glad to inform you that we will use your red lead and 
linseed oil for all bridge work. Yours respectfully, 

(Signed) R. D. O'Keefe, 

Sup't of Public Works. 

29 



The Proper Care of Metal Before and After 
Painting 

The application of the right paint is the most vital step in the 
prevention of corrosion, but every other possible precaution should 
be taken. The following points should be carefully observed. 

It is exceedingly important to clean off rust before painting. Rust 
is an accelerator of rusting. It is also apt to cause the peeling of the 
paint. 

Have the surface to be painted as smooth as possible. It has been 
observed that brightly polished steel plates which have been scratched 
corrode slowly, except at the scratches, where they rust rapidly. 
Structural steel makers may some day realize the importance of this 
phenomenon and provide structural steel with much smoother surface 
than now. At present, structural steel is a rough piece of manufac- 
ture. Care should be exercised at the mill, however, to produce as 
smooth and clean a product as possible. Then the responsibility is 
upon the contractor to keep it so. 

The practice of throwing iron and steel members on the ground 
and allowing them to be covered with dirt and refuse cannol be 
commended. They should be handled with care and placed on 
proper supports. As far as possible they should be kept under 
cover, unless they are to be used within a comparatively short time. 

For years the practice of giving structural steel one coal of pro- 
tective paint before it left the shop held universal sway. Of late, 
however, the custom has been questioned, and many architects and 
engineers are having the steel delivered unpainted. The n< v. idea 
has much to recommend it- two considerations especially. The first 
is, thai a certain amount of weathering is desirable to rid the iron ol 

mill scale. The other is, that shop coats are g< m i.,ll\ | il ; , done 

by cheap labor and really do more harm than good, because thej 
cover up the evidence of poor work in the matter of cleaning the 
metal. In case there is no shop coat, the first painting should be 
done just before assembling begil 

Scale ami all other foreign material must be remo • paint- 

Che relative value of the sand-blast, wire I. rush and pickling, 
as methods lor cleaning, are discussed elsewhere in tin- booklet. 

Little can be done on a structure iring equality ol 

Miriace conditions that is, | ., (IH Ll | | p|j) 

can he done should be done, and where palpablj different condil 

such as where wrought iron rivets and bolts are u~<<\ on I'm 
seller st(>rl memb precaution should be taken with the 

painting at such points. 

lo paint is absolutely imp. - , h ;. 

therefore worth w\ p the moisture contents oi the . 

1 Ins has particular ref< 

1 structural w< , , .,, r;ilI) ., 

30 



might otherwise collect should be made to drain as nearly dry as 

! I ays and viadu nic and other acids are apt 

rhifl should !>«■ prevented practicable by mechan- 

It Li very important to protect bri inst the 

sail drippings from refrigeral For the saline solutions 

apt i ite corrosion. The same caution -dmuM be obse 

in all other places phere salt water is apl to conic in 
pain|ed □ 

I ' - ring for Painting 

.In i before b embling begins all parts of th<* mrt.il win. I 
to I,. ! thai i which cannot I" 

. ,1 after erection should In- i hoi 

brushe and ind al leasl two coats of red lead should be 

applied to the e m fa< 

\\ bile i be use <»f tin- sand bis 

quipped or are wil 
1 1,.,! i .M, be done al presenl is to in i i upon thon 
wire brushes and with the assistance p< tI 

cold clii • I I 
>n[) , | tetenl in spcct< I 

follow cleaning. 

i tion <>f proper men i<> do the cleanii 

,11 importance 1 be n m< n h< »uld !>«• imp 
I heir work, u hich should be ipe< iali i 
I 
placing tin- whole in the l be employers of ui 

iuse <>!' much bad work i 
he done separately by rm 

I J] articles, pickling in uilpl 

i Heni method, i are to be lal en 
| ,n ofl the iron and tl 
until read} to paint I I" follow ing method i 
I lip the b 
I 
minul i i" hot ten p 

water; then in hi 

i; rom the I 

brush ci< lb • ,,r - l[ * the 

omit 

o put them di 
milk o! lime, drj quickl) . and * hei 
bu1 such things as pipes cannot be cleaned ii 
impi 
when drj ■ »H b at. 



T 

II 




"gPfflilBl fir 

•••nip* isi 








Prominent Users of Red Lead 

The railroads of the United States are practically a unit on the 
use of red lead for the protection of iron and steel structural work. 
Of course, most of them are using more or less of other materials all 
the time in a spirit of investigation. Cheaper paints are being offered 
continually and the desire for economy dictates that thorough tests 
shall be made wherever there is reasonable promise of obtaining good 
results for less money. It is the more remarkable, therefore, that an 
admittedly high-priced material holds its own against all comers. 

The Railroad Companies 

The New York Central and Hudson River Railroad Company uses 
red lead exclusively whore no chances are to be taken. Its engineers, 
under dire, lion of Mr. Noel C. Carpenter, engineer in charge of 
structures, have made very extensive tests in recent years to deter- 
mine the relative merits of various materials, and have come to the 
conclusion thai nothing od for a protective coating as red load. 

Consequently, -hup coats the protective paint- on all important 
structural iron and steel work, whether for bridge or buildings, are 
red lead. Finishing coats vary according to conditions to be met. 

Most of the other large railroads also use red lead for protective 
coatings. 

In a series of exposure tests of structural steed paints conducted 
recently by Westinghouse, Church, Kerr and Company, Mr. Cloyd 

M. Chapman, in the report made on the result of these tests, 
"There i- one other point which stands out prominently, and that is 

iIm durability of the group of red-lead primers. Yen interior paints 
were used for the second coat on many of the plates in this group 
and yet tin- average is well up with the 1 

The Federal Government 

The United States Government is a big user of red lead. The 
Navy Department uses tons annually, while on public buildup 
all kinds red lead i> specified for the protection of the structural metal 
,vorl VI the Brooklyn Navy Yard, where a great deal of repairing 

of ships i s done, an officer said: "We find that if a ship has once been 
painted well with red lead, little is required thereafter but to touch 
up abrasions in the outer coat. The protective coats of red lead are 
generally found intact." 

Great Lake Fleets 

A number of steamship companies maintain an immense fleet of 
big freight ships on the I rreal Lakes for carrying ore arid other material. 

er exhaustive experiments, these great corporations have aban- 
doned all other protective paints and arc using red lead exclusively. 

33 



den! <»f a 3 \\ hich builds manj of the 
: 

1 red 1< ad upon 

steel ship all 1 1 indentations thai maj be 

. filled n utely th< 

Citj New \ ork 

1.1I I. ill for building and main 

km I I1.1t of in.iliN 

lead 
ution 
I. I I's Island 

1 1 M 

\ ialitj in Rnl Lead 

hi. ii 

1 
1 

1 
1 






composition Pb s O«; the total amount of lead present shall not be less 
than 89 per cent., of which not more than one-tenth of one per cent, 
shall be present as metallic lead. The color shall be a clean and pure 
tint. The red lead shall be of the fineness that when washed with 
water through a No. 19 silk bolting cloth, not more than one per 
cent, shall be left on the screen." 

Our red lead more than fulfils these strict requirements, which 
accounts for its general use by all large and discriminating consumers. 
It .is the finest and most highly oxydized red lead on the market. 
We welcome all such tests on the part of buyers and willingly co- 
operate to obtain the best results possible in the painting of structural 
steel. 

Mixing and Applying the Paint 

General Cautions. — Where parts of iron and steel are unusually 
exposed to corroding or abrasive influences, they should receive extra 
attention in the matter of painting and preferably an extra coat 
should be applied to all such places. Thus all bolts, rivet-heads, 
all edges and all corners, should have an extra coat of protective 
paint so that at these points the paint may be thicker than where 
the surface is simply flat, and therefore not subject to especially 
destructive influences. 

All parts in contact should be flushed fully with paint, as it is at 
such points that corrosion is apt to be especially insidious. Engineer- 
ing construction should provide for the accessibility of all parts for 
the purpose of painting. 

In all cases the application of the paint should be done by com- 
petent workmen, using round brushes wherever practicable. The 
round, pound brush is an excellent type of brush to use. 

The paint should be of such thickness as to require a strong arm 
and wrist to brush it out. 

Structural Iron Work for Buildings. — In buildings, struc- 
tural iron and steel are generally encased in brick or concrete. We 
have already called attention on page 23 to the advisability of paint- 
ing structural iron and steel which is so encased. All such structural 
metal work should receive three coats of red lead paint, and in addition, 
such touching up of edges and rivet -heads and bolts as may be neces- 
sary to thoroughly protect these especially exposed parts. The 
first coat should be of pure red lead and linseed oil (Formula No.l). 
The second coat should be red lead and linseed oil with an ounce 
of lamp black in oil added for the purpose of changing the tint. 
(Formula No. 2.) The third or finishing coat may be a darker red 
lead coat, (Formula No. 4), a dark olive (Formula No. 7) or it may 
be a black coat of finely ground graphite or lamp black (Formula 
No. 6). The addition of a small percentage of varnish to this finish- 
ing coat will improve its quality. 

35 



Bridges, Viaducts and 1 H - ructural iron and 

• [ s on i ited roads and all 

similar structures should receive the same treatmenl as described 
iron work; except thai they should have four coats instead 
of three, consi two protective coats of red lead and In 

oil Formulas I and I) and two finishing coats The finishi 
color desired, and material should be ch< 
ircumstani I inishing Painl 

\{, firsi finishing coal diould be put on somewhat flat • 
while the final ' aould l,r ' 

: |n the proper painting of inaccessible parts b< 

In the painting of iron and steel in su ime 

lie mould be ol nd \ iadu< 

ept thai the bases of all column 
should h i of paint. The fii mould b< 

I I 

uctural Iron Work foi B 
white fini red. In su< ■!• 

be of whin- lead in linseed oil, mixed accordi 
hould be white lead in lins< 
io Formula No M>. 

[f an enamel finish is desired on top of thin fourtl 

I nulla \<> II 

The columns and verti< al sup] 

, fifth coat, should receive thn • 
oil, th< to i and third being mixed a< 
the econd Formula 

lift!, 

lo 

D, , o Iron W< I 

ftnc j rk should be p 

ducts and el e finishin 

on the d< demands The firsl finishin 

tined with lamp black, .lark oli 

I k I now n l>> U I 

h i: i l 

roof .li.mlil I- 

underneath, n< It would be Rood pi 

on building papei I tin shoul 

■ I S its under 

mould be 
rosin and other fluxii 

land and 
iff with « lied perl 




U ilh R,d Uad 



rinsed cL an and dried. When this is done it will be found that the 
paint will adhere to (In- metal, and it should have two coats of pro- 

e paint. Formulas Nos. 1 and 3.) The finishing coat ma 

a red lead paint with from four to sixteen ounces of lamp black to 

the gallon (see Formul V and 5), or any good paint which 

will [ tint desired. Formula No. 5 gives a rich brown and 

.Me, l>ut in specifying be careful that an iron-oxide 

I is not substituted. The latter will imitate the red lead and 
lamp l.l ... ■ I v in appearance but is not so durable. 

Pai G inized I Galvanized iron is sheet iron 

ed iMi /p.. I., dipping or by means of galvanic or electric action. 

The proc( md is used in an attempt to protect the 

from con Phe method is unsatisfactoi 

and it i found necessary to paint galvanized iron the same as 

ot h< i foi iii of i he metal. 

I I i' the fad thai it can be soldered and • 
therefore be used for cornices. Its greal disadvantage is that, while 
it requin painting, it resists paint. Unles illy done 

t be besl paint u ill peel from it . 

Where practicable, it is a good plan to let the ron 

weather until it has developed a tooth, then clean the surface with a 
brush, t frequently impracticable, how< I the 

following method of preparing the surface is n 

I many excellenl painters, although our nun experiments with 
ive m>t b iniformly successful as to , 

■ sement 

In one gallon of soft water di 
chloride, copper nitrate ami sal ammoniac, then idd I 
of crude hydrochloric acid rhis must be don.- in 

never in tin or o1 her metal recepl a< le ^ppl 
, with a wide, Hat brush. The land and soap-suds 
immended for tin roofs is also applicable, and is to be 
mended. 

Steei Shi ps. The bot toms of steel \ i 

bunkers, chain lockers, and in fad all metal parts of vessels, si 

first be freed from diri and rusl and then b. 

lead paint, mixed according to Formula No I I Id be 

►wed, when dry, with a coat of red lead paint to which 

of lamp black and oil has been added. (Formula 
of pure red lead and oil, mix* 

should be next applied, unless for an} reason a darl • 

in which case an} of the finishing paints, recommended u 

heading below . maj be us< 

'The interiors i olds and other tn- ihould 

be treated thi s bottoms except that in n 

i ither lighter or darker hue are desired. The finis] 
spoken of ah n ailable foi these purposes I 

popular treatment now being \ 



what would otherwise be a dark place. This is to apply over the 
red lead coats a coat of red lead mixed with white lead in the pro- 
portions of two parts red lead to one of white lead. Sei I ormula 
No. l c 2.) A large number of steamship companies, especially on the 
Great Lakes, are using this formula. 

Finishing Paints 

When iron and steel have had a sufficient number of coats of 
good protective paint, the problem is to select suitable finishing 
paints. Generally speaking, any good paint can be applied o 
suitable foundation. By good paints we mean paints that, sel< 
as to color for artistic reasons, are reasonably impermeable and 
contain no actually deleterious constituents. If the paint is to b< 
exposed out of doors, more care should l»< exercised Is the selection 
of the paint to be used than if the paint is not to be exposi d 

It can be considered good practice t<> have the finishing coat of 
a color close to that of the original iron; that is, if the two 01 more 
protective coats start as red, one or two finishii of black paint 

on top of this would ensure fairly complete protection and covering 
of the metal. The black paint could not be applied imperfectly 
without such imperfect application becoming immediately noticed 
I.n the showing through of the red protective coatii 

Where the iron and steel are exposed, the kind of finishing paint 
to use depends upon the color desired. 

For railroad bridges and structures similarly • 
colored paint is often preferred. I rati e p it is 

often desirable to use a dark olive. For interior work, enamel paints 

ometimes used; in which ease, white had or zinc enamels ar< 
be preferred to those made from lithopone. 

mall amount of varnish is -ometimes used also in other finis) 
paints besides enamels. There is no objection to this, as it adds 

hardness and impermeability to the coat. It is. however, in 

that such varnishes only be used as are in them ifficiently 

durable and elastic to stand the kiml m- lor which the paint 

In certain places, such as train sheds, where tin not on 

portant, ii has been difficult to obtain ection <>n 

nit of the sulphur in the engine smoke; and in such cases Lhi 

ection on record has been obtained bj applying, ovei Lb 

wet paint, sheets of thin paraffin p this 

also a .lint . 

Tin r hich d< be kind <»i paint 

finishing paint that \\> 
of the sul that, win I foundat 



Tints for Finishing Coats 

In cases where decoration is important and especially where the 
painted iron work should be brought into harmony with the sur- 
rounding color scheme, it is very often desirable to use white or 
light tints. In all such cases pure white lead and linseed oil is the finish- 
ing paint to use. These materials make the most durable finishing 
paint for average conditions, and, by using with them the proper 
tinting colors, any desired tint or shade can be obtained. 

White lead and linseed oil are especially adapted for use over 
red lead and linseed oil, because linseed oil dries much the same 
with these two pigments and therefore the two paints make a homo- 
geneous film, as regards the dried-oil component. 

A word of caution should be given upon the use of red lead and 
lamp black to form a brown. (Formula No. 5.) This gives a color 
which can be very easily imitated by the brown oxides of iron and 
care should be exercised that the latter is not substituted for the 
more durable red lead. 



BRIEF SPECI FI( , ATM )X F( )R PAINTING 
IRON AND STEEL. 



All iron and steel shall be scraped clean of 
mill scale and dirt and painted with two coals 
of paint made of John T. Louis & Bros. 
Company's pure red lead and pure linseed oil, 
mixed 33 pounds of red lead to the gallon of 
oil. 

The second coat shall contain 4 ounces of 
lampblack to the gallon of oil. The finishing 
coats shall be of John T. Lewis & Bros. 
Company's red lead or John T. Louis & Bros. 
Company's white lead and linseed oil, tinted 
according to color scheme stipulated. 



(Formulas referred to will be found on pages 42 and 4 3. ) 

41 



Formulas for Mixing the Paint 

Priming and Bods * oate 

D PRIMING I OA l 

■ 






























Formulas for Mixing the Paint— Continued 

Finishing Coats 

No. 6— BLACK (OAT. 
A good black paint of finely ground 
graphite or lamp black with a small 
percentage of varnish added. 

v : DARK OLIVE. 

10(1 pounds pure white lead; 

l(i pounds French ochre; 

40 pounds medium chrome yellow ; 

19 pounds lamp black in oil. 

(This gives the properly tinted pigment 
Linseed oil and drier must be added in 
sufficient quantities to bring it to painting 
consistency 

No. 8. -WHITE GLOSS FINISH FOR EXTERIOR 

:J ] 2 to 4 1 ■_> gallons raw linseed oil; 
1 pint pure turpentine; 
1 pint pure turpentine drier. 
100 pounds pure white lead. 

(This formula makes 6.56 to ) 56 gal. paint i 

No. 9.— WHITE GLOSS FINISH FOR EXTERIOR. 
(Slightly Hatter than No. 8). 
23^ gallons linseed oil; I ' \ boiled oil, '-'.■< raw oil or all raw linseed 

oil with ' j pint turpentine drier added 
1 gallon turpentine; 
100 pounds pure white lead in oil. 

/ h is fp nun hi makes 6. SI gal. paint. 

No. 10.— WHITE FLAT FINISH FOR INTERIOR. 

% gallon raw linseed oil; 

1% to 2 gallons pure turpentine; 

1 pint pure turpentine drier; 
100 pounds pure white lead. 
(This formula makes )..'>} to 5.18 gal. paint. 1 

No. 11. WHITE ENAMEL FINISH FOR INTERIOR. 

1 gallon light enamel varnish; 
3 pounds pure white lead. 
Break up the white lead first with a little turpentine to a thick paste, then mix well 
with the varnish.) (This formula makes 1.08 gal. paint.) 

No 12.— SHIP HOLD FINISH. 
1 gallon linseed oil; (V£ boiled oil, -3 raw; or all raw oil with ! -j 
pint turpentine drier added I 
22 pounds pure red lead; 
11 pounds pure white lead. 

(This formula makes 1.6 gal. paint.) 

Note — The formulas for white finishes can be adapted to any tint desired by putting 
in the proper tinting material and adding thinners equal to one-half the weight of the 
tint tug material. 

N<> 1 1 When red lead is mentioned in these formulas, dry red lead is meant. On th< 
contrary, when white lead is mentioned, white lead-in-oil, as usually furnished to the 
trade, is infant. 

4? 



INDEX 



Alkalies in paint 

Alkaline solutions for preserving iron 

Architects' special interest in painting metal work 

Asphaltum 

Available paints 



7 

7 

21 

IS 

11 



H 

Bascule Bridge over Schuylkill River at Point Breeze, Philadelphia 
Battleships North Dakota and South Carolina 

llattleship Iowa . 

Black finishing coat 

Boats, Steel 

Knits 

Bridges, Painting <>f 

Bridges, viaducts and elevated roads 

Brown for finishing coal 

Hunkers, Coal 

( 

< arli. .n and graphite 

< Carbonate of calcium 

< larbonic acid 

< !are <>f metal before and after painting 

Refrigerator 
Steel 

< austic lime 
( ellars 

( emenl 

at, I>«»,s Red Lead form a 
dng of paint, ( lauses of 

< hemical analysis of Red Lead 

< lifotuic acid solutions 

Cleveland Trust Co. Building, Cleveland 
■ paint important 
te f<»r protecting iron 

< oncrete, Steel imbedded in 

es and other galvanized iron work 
ling tendency of various metals 
I 

sion, Red Lead as inhibitor of 

< orrosion, Relative standing of metals in reaisl 

< racking of paint, < !auses <»f 

I) 
•i ir.ni and Bteel 
irou work 
Derr 
Dewej , U. S. N tvy'a Floating Dry I I 

E 

Elect r,. I 

Electri 

I 

I ted Structure of Philadelj i; Philadelphia 

I 

metal pain! 



... 2-4 

!6 

18 

in. 13 

. . . 2G 

to 

;: 
ii. 12 



i l 
15 

SI 

so 

7 

IS 

. IS 



7 



10 



INDEX— Continued 
F 

Factory equipment $;, 

Fatigue in steel 7 

Fences 25,37 

Field and laboratory tests 

Fineness of Red Lead . 16, 17 

Finishing Paints !», pi, i-2 

I 1 Kscapes 

First National Bank, Cleveland 6 

Formulas (paint) for all protective purposes 

(. 

Galvanized iron, Painting 

Gasometers and stand-pipes .25 

Gates >;, 

General qualifications of paint \) 

Getting ready to paint 

Good paint for metal, general requirements .... .... .9 

Government Building, Omaha s 

Graphite and carbon ] 1 

Grilles . . . 

Gutters .... 30 

H 

Holds, Cargo 

Hotel Sinton, Cincinnati 12 

How much Red Lead to the gallon 

How mueh Red Lead to the ton of metal .27 

Hulls, ships 

I 

Impermeability of Red Lead Hi 

Inhibitor of corrosion, Red L<-a<l ;in 15 

Insulator, Red Lead as 16 

Insurance rates 

Interior metal work . 

Iron oxides 15, 2 

Iron — why painted T 

Iron and steel brills - 
Iron and steel decay 

L 

Laboratory and field tests -'; 

Linseed oil — alone and with a pigment It 

Linseed oil — effect on Red Lead 21 

Litharge 19,21 

Lithopone 

Lockers 

I."v\ Grade Division, Pennsylvania R. R., Pequea, Penn. 24 

M 

Machinery 

Manganese, as a drier 21 

Metals, Good paint for !» 

M Is — relative standing in resisting corrosion . . 

Mel ds '■■ndency to corrode .... 

Mi til roofs . 

M< 1.1I surface — preparing it to be painted SI 

M tal work. Interior . . 

4s 



IB 



INDEX ^ ontinued 






\ 







































INDEX— Continued 

- 

solutions :il 

Mast 

Ship-hold finish formula 

p-coats 

Side sheathings, Tin 

- 21 

Specifications of I S Navy for Red-lead paint 

l-pipes 

Steel aooth surface on 

Steel bridges, Painting 

I 
Steel < ars 

I bing paints for 
imbedded in concrete 

n, [mportance of 
Steel ships and boats 

i ural iron and steel 
Structural iron wm-k fur buildings 
Structural Work ou 1> • of ^nshe < Ihesed Synagogue, < leveland 

Sulphuric acid 



:i 



Tanks 

I i: I 

I | orrosion 

id tin side sheathings 
Tinted coal formulas 

i for finishing coal s 

Making <>f 
Train sheds 

I ks 

I urpentine 

I 
l: I 
i of Red Lead 

mitj ni Red Lead 

nment large users of Red Lead ou vessels 
i 3. Na Department specifications 



\ 



\ 

I 
\ I in 

\ iaducts 



\\ li.ii i onstitutes a good paint 
•' »t finish for interior w< 
loss tini>h for exterior esq 
\\ 
S\ ■ irth Building . . . 





10 














w 








k i Formula I 


19 













PRODUCTS MANUFACTURED BY 
NATIONAL LEAD COMPANY 



PAINTERS' MATERIALS 

White Lead, Dry Red Lead 

White Lead in Oil Colors, Dry and in Oil 

Linseed Oil, American and Calcutta, 
Raw, Boiled, Refined, Varnish makers' 

BEARING METALS 

Phoenix Metal Babbitt Metals 

Pressure Die Castings 

PLUMBERS' MATERIALS 

! Pipe Leadamant Pipe 

Block Tin Pipe Lead Traps and Bend- 

Tin-lined Lead Pipe ^..lder 

Soldering Flux 

PRINTERS' METALS 

Linotype Metal Stereotype Metal 

Monotype Metal Elect rotype Metal 

( \WERS MATERIALS 

Bar Solder Ribbon Solder 

Wire Solder Triangular Soldei 

5 ldering Flux 

LEAD OXID] - 

Red Lead Rubbermakei s' ( brides 

Li Hi, \ arnishmakers 1 Oxid< - 

( Grange Mineral I tnelmakei 

Glassmakers 1 Oxides Potters' Oxides 

( 'olormakers 1 Oxid< \> i iimulator < Oxides 

MISCELLANEOUS LEAD PRODI < TS 

Sheet Lead Lead \\ ire 

Glazu l Lead Sash \\ eights 

Bar I Piano Key L 

• J \l l{ .\L PRODI < rs 

B vn Sugar of Ij Linseed Oil Cake and Meal 

Wlr S I • ad I I nl 

Nil Soda 

48